Control of undesirable vegetation



3,436,207 CONTROL OF UNDESIRABLE VEGETATION Edward J. Soboczenski, Chadds Ford, Pa., assignor to E. I. du Pont de Nemours and Company, Wilmington, Del., a corporation of Delaware No Drawing. Filed Feb. 23, 1965, Ser. No. 434,701 The portion of the term of the patent subsequent to Feb. 15, 1983, has been disclaimed and dedicated to the Public Int. Cl. A01n 9/22, 7/00; C07d 51/34 US. Cl. 71-92 9 Claims ABSTRACT OF THE DISCLOSURE The invention relates to the use of 3-substituted-5,6 substituted 2,4 pyrimidinediones as herbicides for the control of undesired vegetation. Typical compounds useful in the method of this invention are 3-cyclohexyl-5,6- dihydro 7 methyl-S-cyclopenta[D]pyrimidine-2,4(1H, 3H)-dione and 3-sec-butyl-5,6-dihydro-7-methyl-5-cyclopenta[D]pyrimidine-2,4 lH,3H)-dione.

This invention relates to novel 3-substituted-S,6-substituted alkylene-2,4-pyrimidinediones and to compositions and methods employing these compounds as herbicides.

More particularly, this invention is directed to novel pyrimidinediones of the formula:

R is alkyl of 1 through 10 carbon atoms,

atoms, (substituted cycloalkenyl)alkyl of through 14 carbon atoms, cyano or m A N-- which is a cycloimino group of 2 through 14 carbon atoms having a maximum of 3 hetero atoms.

R R and R are the same or different and are selected from the group consisting of hydrogen, alkyl of C C haloalkyl of C C alkoxy of C -C alkylthio of C -C and alkenyl of C -C Y is halogen including chlorine, bromine, fluorine and iodine;

n is 3, 4, or 5; and

m is 0 or 1; with the proviso that when R R and R are hydrogen, m is 1.

As is well known in the art, herbicidal compounds frequently are utilized in the form of a herbicidal equivalent salt, addition compound, or complex derivative United States Patent Ofice 3,436,207 Patented Apr. 1, 1969 thereof for some formulating or handling advantage the derivative may provide over the compound per se. Similarly, it is to be understood that also included within the scope of this invention are salts, addition compounds, and complexes of the pyrimidinediones of Formula 1 which can be formed from Lewis bases and acids and which exert a herbicidal effect similar to that of the uracils per se. Lewis bases and acids are generally described in the following texts: 1) J. Hine, Physical Organic Chemistry, McGraw-Hill Book Company, Inc., New York, 1956, chapter 2; (2) W. F. Luder and S. Zuffanti, The Electronic Theory of Acids and Bases, John Wiley and Sons, Inc., New York, 1946; (3) E. S. Gould, Mechanism and Structure in Organic Chemistry, Holt, Rinehart and Winston, New York, 1959, Chapter 4; (4) E. M. Arnett, Progress in Physical Organic Chemistry, vol. 1, edited by S. G. Cohen, A Streitwieser, Jr., and R. W. Taft, Interscience Publishers, Inc., New York, 1963, chapter entitled Quantitative Comparisons of Weak Organic Bases; and (5) G. A. Olah, editor, Friedel-Crafts and Related Reactions, volumes 1 and 2, Interscience Publishers, Inc., New York, 1963.

Non-limiting illustrations of compounds shown in the above texts which can be used to form salts, addition compounds, or complexes with the pyrimidinediones of Formula 1 for purposes of the present invention are:

Bases sodium hydroxide potassium hydroxide lithium hydroxide calcium hydroxide magnesium hydroxide barium hydroxide strontium hydroxide ferric hydroxide manganese hydroxide quaternary ammonium hydroxides primary, secondary and tertiary amines heterocyclic amines guanidines amidines phenols cresols naphthols Acids Friedel-Crafts catalysts halogenated benzoic acids mineral acids organic sulfonic acids halogenated aliphatic acids halogenated aryloxyaliphatic acids organic aliphatic and aromatic acids In Formula 1 the term substituted alkyl is intended to include such radicals as bromoalkyl of 1 through 10 carbon atoms chloroalkyl of 1 through 10 carbon atoms hydroxyalkyl of 1 through 10 carbon atoms alkoxyalkyl of 2 through 12 carbon atoms alkoxy carbonyl alkyl of 3 through 12 carbon atoms dialkyl amino alkyl of 3 through 12 carbon atoms and cyanoalkyl of 2 through 10 carbon atoms Similarly, the term aryl and substituted aryl embrace radicals such as phenyl naphthyl o-biphenylyl pyridyl chlorophenyl bromophenyl alkoxyphenyl dichlorophenyl dibromophenyl trichlorophenyl alkylphenyl of 7 through 11 carbon atoms dial kylphenyl of 8 through 12 carbon atoms. chloroalkylphenyl of 7 through 10 carbon atoms nitrochlorophenyl nitrophenyl dichloronitrophenyl chloroalkoxyphenyl of 7 through 11 carbon atoms trifluorornethylphenyl alkylnaphthyl of 11 through 16 carbon atoms chloronaphthyl tetrahydronaphthyl and indenyl The terms aralkyl and substituted aralkyl are intended to include such radicals as furfuryl benzyl phenylalkyl of 8 through 11 carbon atoms (total) chlorobenzyl dichlorobenzyl alkylbenzyl of 8 through 11 carbon atoms (total) dialkylbenzyl of 9 through 13 carbon atoms (total) nitrobenzyl alkoxybenzyl of 8 through 11 carbon atoms (total) and naphthylrnethyl The terms cycloalkyl, cycloalkenyl, cycloalkyl alkyl, and cycloalkenyl alky will include cyclopropyl cyclohexyl cyclohexenyl cyclohexylalkyl cyclohexenylal'kyl cyclopentyl cyclopentenyl cyclopentylalkyl cyclopentenylalkyl norbornyl norbornenyl norbornylalkyl norbornenylalkyl bicyclo(2,2,2)octyl bieyclo(2,2,2)octenyl bicyclo(2,2,2)octylalkyl bicyclo (2,2,2) octenylalkyl cyclopropyl cyclobutyl cyclobutylalkyl cyclobutenyl cyclobutenylalkyl hexahydroindanyl tetrahydroindanyl hexahydroindenyl hexahydroindenyl alkyl tetrahydroindanyl alkyl hexahydroindanyl alkyl hexahydro-4,7-methanoindenyl tetrahydro-4,7-methanoindanyl hexahydro-4,7-methanoindanyl hexahydro-4,7-methanoindenyl alkyl tetrahydro-4,7-methanoindanyl alkyl hexahydro-4,7-methanoindanyl alkyl decahydronaphthyl decahydronaphthyl alkyl tetrahydronaphthyl tetrahydronaphthyl alkyl decahydro-l,4-methanonaphthyl decahydro-1,4-methanonaphthyl alkyl octahydro-1,4-methanonaphthyl octahydro-l,4-methanonaphthyl alkyl decahydro-l,4,5,8-dimethanonaphthyl 4 decahydro-1,4-5,S-dimethanonaphthyl alkyl octahydro-l,4-5,8-dimethan0naphthyl and octahydro-l,4-5,8-dimethanonaphthyl alkyl These cyclic substituents can be further substituted with alkyl groups containing 1 through 4 carbon atoms, methoxy, chlorine and bromine.

The term cycloimind is intended to include such radicals as @QEJ where R is alkyl of 1 through 4 carbon atoms or CH CH OH and y is 0-4.

It is obvious from the above that the term cycloimino as used herein includes hetero atoms but it is intended in accordance with the invention that the number of hereto atoms in the group of the 3-position of the pyrimidinedione ring does not exceed three.

I Utility The pyrimidinediones of Formula 1 and their various salt, complex, and addition compound derivatives are novel herbicides for the control of undesirable vegetation and quite surprisingly exhibit the unusual capability of having a highly potent activity in general weed control sites such as railroad rights-of-way, roadsides, fence rows, and areas adjacent cropland and industrial plants and in addition having a selective herbicidal activity in crops such as in sugar cane so that weed control can be accomplished without damage to the crop.

The concentrations at which the compounds of this invention are to be used will vary according to the result desired, the type of vegetation, the formulation used, the mode of application, weather conditions, foliage density, and other similar factors. Since so many factors play a role, it is not possible to indicate a concentration suitable for all situations. Generally, when they are used "for pre-emergence treatment in crops, these pyrimidinediones are used at concentrations of at least about 0.5 pound of active ingredient per acre. Concentrations of from 0.5 to 3 pounds per acre are preferred.

When used in non-crop applications, the pyrimidinediones are used at concentrations of from to 30 pounds of active ingredient per acre. The optimum concentrations to be used in any particular application will be readily apparent to one skilled in the art.

The preferred compounds for use according to this invention are the compounds of Formula 1 where R is an alkyl or alkenyl radical containing 3 through 6 carbon atoms, phenyl, substituted phenyl, cycloalkyl radical of 3 through 10 carbon atoms or cycloalkenyl radical of 4 through 10 carbon atoms,

n is 3, 4, or 5,

R is methyl or ethyl R and R are H and their sodium, and potassium salts, nitrogenous base addition compounds, phenol complexes and acid addition compounds.

PREPARATION OF COMPOUNDS The pyrimidinediones of Formula 1 can be prepared according to the following equations:

In Equations 2 and 3, R, R R R Y, m and n have the same meaning as in Formula 1; R is an alkyl radical of 1-6 carbon atoms, H is an acid, and B- is a base.

The reaction sequence consists of two steps: first, the acid catalyzed condensation of a l-substituted urea with a substituted alkyl 2-cycloalkanone-l-carboxylate to give the ureido intermediate; and, second, the alkaline ring closure of this intermediate to the salt of the pyrimidinedione product, followed by treatment with acid to liberate the free pyrimidinedione.

The first step, illustrated by Equation 2, is best carried out by dissolving or suspending the l-substituted urea in a solvent such as xylene, benzene or a mixture of benzene and dioxane, and heating to reflux. To this solution is then added a mixture of the acid catalyst in slight excess of the alkyl 2-cycloalkanone-l-carboxylate. Suitable acid catalysts are p-toluenesulfonic, sulfuric, benzenesulfonic, phosphoric, polyphosphoric, formic, chloroacetic, or Lewis acids such as BF and AlCl The mixture is stirred and heated to reflux until the Water, split out during the reaction and collected in a suitable apparatus, ceases to be given off. The clear solution is decanted or filtered and then concentrated to give the intermediate ureido derivative.

In the second step, illustrated by Equation 3 the ureido intermediate is dissolved in alcohol containing a slight excess of base, preferably an alkali metal alkoxide or hydroxide, and the solution is refluxed for a short time. This step efiects the ring closure. The salt of the pyrimidinedione is obtained by concentrating this solution to dryness. The free pyrimidinedione is prepared by acidifying an aqueous solution of the salt, and then isolating the solid. For the most part the compounds prepared by this route will consist of a mixture of optical isomers.

Many of the cyclic keto esters needed to prepare the novel pyrimidinediones of this invention may 'be obtained by Dieckmann cyclization of substituted adipic, pimelic, or suberic acids. All of the ring sizes encompassed by this invention may be included according to this process. The diacids in turn may be purchased or prepared according to classical methods of organic chemistry from such readily available starting materials as substituted phenols or butadiene dimers. Cyclic keto esters having ring sizes of 5 and 7 carbon atoms are most easily prepared by these processes.

According to the above, substituted phenols are hydrogenated to the corresponding cyclohexanols, which are then oxidized to the corresponding adipic acids. Details for carrying out these oxidations may be found in J.A.C.S., 52, 3235 (1930); U.S. 1,921,101; Ger. 854,507; J. Chem. Ed., 10 114 (1933); and C.A., 31 3875 (1937). The butadiene dimers may be further substituted and then likewise oxidized to the substituted suberic acids.

Another source of these cyclic keto esters is the carbonylation of available cyclic ketones according to the following references.

(1 J.A.C.S., 70, 2287 1948 2 J.A.C.S., 70, 497 (1948) 3 J.A.C.S., 66, 1768 1944 4 J.A.C.S., 69, 2677 (5) J.A.C.S., 70, 2884 These procedures are especially useful, though not restricted to, cyclic keto esters having a six membered ring. Alkyl substituted cyclic ketones possessing a six numbered ring are readily available from both synthetic and natural sources. A wide variety of cyclic keto esters is, therefore, automatically made available by this technique.

Another source of substituted cyclic keto esters arises by carrying out one or more reactions on those available cyclic keto esters which are either unsubstituted or not as highly substituted as desired. 3-alkyl substituted cyclic keto esters are made especially available by this procedure. For further details see:

(1) I.O.C., 29, 2781 (1964), and (2) J.C.S., 1942, 559.

Still another source of these intermediates is from the Kolbe or modified Kolbe reactions which are used to produce substituted salicylic acids. These acids are esterified by routine procedures. They are reduced by hydrogenation to the corresponding cyclohexanol carboxylic esters and then mildly oxidized to the intermediate cyclic keto esters.

Finally many halogenated compounds within the scope of this invention may also be prepared by halogenating a previously prepared substituted pyrimidinedione. For example:

Substitution by the halogen takes place most easily in the positions allylic to the double bond.

Chlorination may be carried out either with chlorine per se or sulfuryl chloride. When direct chlorination is desired solvents such as acetic acid are useful for promoting and moderating the reaction. The reaction may be carried out most conveniently from room temperature to the boiling point of acetic acid. A higher percentage of allylic chlorides is obtained at the higher temperatures. Chlorination with sulfuryl chloride is less vigorous than. direct chlorination, but may be desirable under certain circumstances.

Bromination to form the substituted pyrimidinediones of this invention may be carried out directly with elemental bromine or with N-bromosuccinimide.

Additional information pertinent to the halogenations described here may be found in Synthetic Organic Chemistry R. B. Wagner and H. D. Zook, pp. 98, 104 (1956).

Metal salts of the pyrimidinediones of Formula 1 are prepared by conventional methods such as dissolving the free pyrimidinedione in an aqueous or nonaqueous solution of at least an equimolar amount of a base or basic salt containing the desired cation. For example, a sodium salt can be prepared by dissolving the pyrimidinedione in water containing an equilmolar amount of sodium hydroxide. The salt can then be isolated from the solution by removal of the water. The pyrimidinedione salts which are not soluble in water can be best prepared by treating an aqueous solution of an alkali metal salt of the pyrimidinedione with an aqueous solution of a water-soluble salt of the metal.

Quaternary ammonium salts of the pyrimidinediones of Formula 1 are prepared by the reaction of the substituted pyrimidinedione with an appropriate quaternary ammonium hydroxide. Since these hydroxides are generally available in solution, the reaction is most conveniently carried out in the same solvent. If the solvent-free salt is desired, it can be easily prepared by removing the solvent.

Alternately, the quarternary ammonium salts can be prepared from the corresponding sodium salts in a dry inert solvent such as toluene or xylene. The appropriate quarternary ammonium halide is then added with stirring and, it necessary, mild heating. The sodium halide which forms is removed by filtration, leaving the quaternary ammonium salt of the pyrimidinediones in solution. If desired, the solvent-free salt can be prepared by removing the solvent, preferably in vacuum.

Additional compounds of the pyrimidinediones of Formula 1 with Lewis bases such as amines can be prepared by mixing together equimolar quantities of an appropriate pyrimidinedione and a nitrogenous base. The mixture is gradually heated, with stirring, until a clear melt is formed. On cooling, the addition compound crystallizes. This product can then be recrystallized from a solvent such as benzene, cyclohexane, nitrornethane, or acetonitrile.

It is sometimes advantageous to use an inert solvent medium to carry out the reaction. Such a solvent moderates the reaction by acting as a heat sink, and allows better control of the reaction, especially if it is being carried out on a large scale. Suitable inert solvents are benzene,

cyclohexane, nitromethane, acetonitrile and dioxane.

When an inert solvent is used, the addition compounds are prepared by dissolving the amine in the solvent and then adding the pyrimidinedione gradually, with stirring. Stirring is continued for from ten minutes to two hours. Mild heating may be necessary. Some addition compounds precipitate and can be removed by filtration. Other addition compounds are isolated by evaporation of the solvent. The addition compounds prepared in this way are suitable for use without further purification, but can be purified by recrystallization if desired.

In some instances, the pyrimidinedione and amine are highly soluble in the inert solvent, but the addition compound is not, and so it can be filtered off pure when the reaction is complete.

Complexes of the pyrimidinediones of Formula 1 with a Lewis base such as phenol can be formed by comelting the pyrimidinediones and phenol in a 1:1 to 2:1 (pyrimidinedioneszphenol) ratio. They can also be formed by codissolving the reactants, in the same ratio, in a solvent such as nitromethane or a mixture of nitromethane and cyclohexane. Process conditions and isolation procedures are the same as those described above for the additional compounds.

8 HERBICIDIAL COMPOSITIONS The compounds of the invention can be prepared for use by incorporating them with adjuvants.

The amount of herbicide in such preparations can vary over a wide range according to need. Generally speaking, they will contain from about 0.5% to by weight of a pyrimidinedione.

Powder and dust preparations can be made by mixing pyrimidinediones of the invention with finely-divided solids such as tales, natural clays, pynophillite, diatomaceous earth; flours such as walnut shell, wheat, redwood, soyabean and cotton seed; or inorganic substances such as magnesium canbonate, calcium carbonate, calcium phosphate, sulfur and lime. These preparations are made by thoroughly blending the active ingredient and the solid. The particles in such preparations should be less than 50 microns in average diameter, preferably about 20 microns.

Water-soluble powders can be prepared by blending a suitable pyrimidinedione with such water-soluble alkaline powders as silicates, carbonates, phosphates, or hydroxides, and optionally with water-soluble diluents such as urea or dextrose.

Granules and pellets can be made by mixing a finelydivided pyrimidinedione with a suitable clay such as kaolinite, montmorillonite or attapu-llgite, Inoistening this mixture with from 15 to 20% by weight of water, and then extru ding the mass through a suitable die under pressure. The extrusions are cut into pre-deterrnined lengths and then dried. These pellets can the granulated if desired.

Granules or pellets can also be prepared by spraying a suspension or solution of a pyrimidinedione onto the surface of a preformed granule of clay, vermiculite or other suitable granular material. If the pyn'midinedione is in solution, it will penetrate into the pores of the granule and so will adhere without the aid of a binding agent when the active material is insoluble in the liquid and is carried as a suspension, it is preferable that a binding agent such as goulac, dextrin, swollen starch, glue or polyvinyl alcohol be added. In either case, the granule is then dried and ready for use.

The pyrimidinediones can also be prepared in liquids. Water and aliphatic and aromatic hydrocarbons, especially those derived from petroleum and having boiling points of from C. to 400 C. are preferred. Hydrocarbons having lower boiling points should not be used because of their undesirable volatilization characteristics and inflammability. These liquid preparations are made by dissolving the active in the liquid, or, if the active is insoluble in the liquid, by milling the components in a *mill such as a pebble mill until the particles have average diameters of from 1 to 50 microns, preferably 5 to 20 microns.

The herbicidal preparations, whatever physical form they take, can also contain a surface-active agent. The surfactant renders the preparations readily dispersible in liquids and improves their action on waxy leaves and the like. For general application, surface-active agents are used in the preparations at concentrations of from about 1 to 10% by weight. Levels of from 0.5 to 6 parts of surfactant for each part of pyrimidinedione, however, give unusual and unexpected results. Preparations having these higher levels of surfactants show greater herbicidal effectiveness than can be expected from a consideration of activity of the components used separately.

The term surface-active agent" is intended to include wetting agents, dispersing agents, suspending agents and emulsifying agenits. Surface-active agents suitable for use are set forth in Detergents and Emulsifiers upto-date, 1962, John W. McCutcheon, Inc., Morristown, NJ. Other surface-active agents which can be used in these preparations are listed in US. Patents 2,139,276; 2,412,510; 2,426,417; 2,655,447; and Bulletin E-607 of the Bureau of Entomology and Plant Quarantine of the US. Department of Agriculture.

The preparations can also contain adhesives, corrosion inhibitors, antifoaun agents, dyes and pigments, anticaking agents, and hard water stabilizers.

The salts of the compounds of Formula 1 are especially advantageous for use as herbicides because many are soluble in water and can be applied as aqueous solutions.

FORMULATION WITH OTHER HERBICIDES The herbicidal compositions of this invention can be formulated to contain two or more of the pyrimidinediones. They can also be formulated to contain other known herbicides in addition to the pyrimidinediones to give compositions which have advantages over the individual components.

Among the known herbicides which can be combined with the pyrimidinediones are:

Substituted ureas 3- 3,4-dichlorophenyl -1,1-dimethylurea 3- 4-chlorophenyl 1 l-dim'ethylurea 3 phenyll l-d itmethylu rea 3- 3,4-dichlorophenyl) -3-methoxy 1, 1 dimethylurea 3 4-chiorophenyl -3-methoxy-1, l-dimethylurea 3- 3 ,4-dichlorophenyl)-1-n-butyl-1-n1ethylurea 3- 3 ,4-dichlorop henyl -1-methoxy-1-methylurea 3- (4-chlorophenyl -1-methoxyl-methy lurea 3- 3 ,4-dichlorophenyl) -1,1,3-trimethylurea 3- 3 ,4-dichloropheny-l)-1,1-diethylurea 3 p-chlonophenoxyphenyl) -1,-1-dimethylurea These ureas can be mixed with the pyrimidinediones in proportions of from 1:4 to 4:1, respectively, the preferred ratio being 1:2 to 2:1.

Substituted triazines These triazines can be mixed with the pyrimidinediones in proportions of from 1:4 to 4:1, respectively, the preferred ratio being 1:2 to 2:1.

Phenols 4-cyano-2,6-diiodophenol and its salts 4-cyano-2,6-dibrornophenol and its salts dinitro-o-sec-butylphenol and its salts pentachlorophenol and its salts These phenols can be mixed with the pyrimidinediones in the proportions of 1:10 to 20:1, respectively, the preferred ratio being 1:5 to 5: 1.

Carboxylic acids and derivatives The following carboxylic acids and derivatives can be mixed with the pyrimidinediones in the listed respective proportions:

2,3,6-trichlorobenzoic acid and its salts 2,3,5,6-tetrachlorobenzoic acid and its salts 2-methoxy-3,5,6-trichlorobenzoic acid and its salts 2-methoxy-3,6-dichlorobenzoic acid and its salts 3-amino-2,S-dichlorobenzoic acid and its salts 3-nitro-2,S-dichlorobenzoic acid and its salts 2-methyl-3,6-dichlorobenzoic acid and its salts 2,3-dichloro-6-methylbenzoic acid and its salts 2,4-dichlorophenoxyacetic acid and its salts and esters 2,4,S-trichlorophenoxyacetic acid and its salts and esters (2-methyl-4-chlorophenoxy) acetic acid and its salts and esters 2-(2,4,5-trichlorophenoxy)propionic acid and its salts and esters 2- 2,4,5-trichlorophenoxy ethyl-2,Z-dichloropropionate 4-(2,4-dichlorophenoxy)butyric acid and its salts and esters 4-(2-methyl-4-chlorophenoxy)butyric acid and its salts and esters 2,3,6-trichlorobenzyloxypropanol Mixed in a 1:20 to 8:1 ratio, preferably a 1:4 to 4:1 ratio.

2,6-dichlorobenzonitrile Mixed in a 1:4 to 4:1 ratio, prefer-ably a 1:3 to 3:1 ratio.

trichloroacetic acid and its salts Mixed in a 1:4 to 25:1 ratio, preferably a 1:2 to 10:1 ratio.

2,2-dichloropropionic acid and its salts Mixed in a 1:4 to 10:1 ratio, preferably a 1:2 to 5:1 ratio.

N,N-di(n-propyl)thiolcarbamic acid, ethyl ester N,N-di(n-propyl)thiolcarbamic acid, n-propyl ester N-ethyl-N-(n-butyl)thiolcarbamic acid, ethyl ester N-ethyl-N-(n-butyl)thiolcarbamic acid, n-propyl ester Mixed in a 1:2 to 24:1 ratio, preferably a 1:1 to 12:1 ratio.

N-phenylca'rbamic acid, isopropyl ester N- (m-chl0rophenyl)carbarnic acid, isopropyl ester N- (m-chlorophenyl carbamic acid, 4-chloro-2-butynyl ester Mixed in a 1:2 to 24:1 ratio, preferably a 1:2 to 12:1 ratio.

2,3,6-trichlorophenylacetic acid and its salts Mixed in a 1:4 to 10:1 ratio, preferably a 1:2 to 5:1 ratio.

2-chloro-N,N-diallylacetamide Z-methyl-6-tert-butyl-N-methoxymethyl-2'-bromo-acetanilide N-isopropyl-N-phenyl chloroacetamide Mixed in a 1:2 to 10:1 ratio, preferably a 1:1 to 5:1 ratio.

Inorganic and mixed inorganic-organic salts The following salts can be mixed with the uracils in the listed proportions:

calcium propylarsonate disodium monomethylarsonate octyl-dodecylammoniummethylarsonate dimethylarsinic acid Mixed in a 1:4 to 4:1 ratio, preferably a 1:2 to 2:1 ratio.

sodium arsenite Mixed in a 1:10 to 40:1 ratio, preferably a 1:5 to 25:1 ratio.

C. lead arsenate calcium arsenate Mixed in a 150:1 to 600:1 ratio, preferably a 100:1 t 400:1 ratio.

sodium tetraborate hydrated, granulated sodium metaborate sodium pentaborate polychlorborate unrefined borate ore, such as borascu Mixed in a 3:1 to 1500:1 ratio, preferably a 6:1 to 1000:1 ratio.

ammonium thiocyanate Mixed in a 1:10 to 20:1 ratio, preferably a 1:5 to :1 ratio.

sodium chlorate Mixed in a 1:1 to 40:1 ratio, preferably a 2:1 to 20:1 ratio.

ammonium sulfamate Mixed in a 1:1 to 100:1 ratio, preferably a 1:1 to 50:1 ratio.

Other organic herbicides The following herbicides can be mixed with the pyrimidinediones in the listed respective proportions:

5,6-dihydr0-(4A,6A)-dipyrido-(1,2-A,2',1'-C) pyrazinium dibromide 1,1'-dimethyl-4,4-dipyridinium di- (methyl sulfate) Mixed in a 1:20 to 16:1 ratio, preferably a 1:5 to 5 :1 ratio.

B. 3-amino-l,2,4-triazole Mixed in a 1:20 to 20:1 ratio, preferably a 1:5 to 5:1 ratio.

3,6-endoxohexahydrophthalic acid Mixed in a 1:4 to 20:1 ratio, preferably a 1:2 to :1 ratio.

D. diphenylacetonitrile N,N-dimethyl-a,a-diphenylacetamide N,N-di-(n-propyl)-2,6-dinitro-4-methy1aniline N-methyl-N-n-butyl-Z,6-dinitro-4-trifiuoromethylaniline Mixed in a 1:10 to 30:1 ratio, preferably a 1:5 to 20:1 ratio.

O- (2,4-dichlorophenyl -O-methyl-isopropylphosphoramidothioate 2,3,5,6-tetrachloroterephthalic acid, dimetl'lyl ester thiomethyl ester of 2,3,5,6-tetrachloro-4-carbomethoxy benzoic acid Mixed in a 1:4 to 20:1 ratio, preferably a 1:3 to :1 ratio.

2,4-dichloro-4-nitrodiphenyl ether Mixed in a 1:10 to 30:1 ratio, preferably a 1:5 to 20:1 ratio.

1-(3,4-dichlorophenyl) -3 ,S-dimethylhexahydro-l,3,5-

triazinone-Z l-phenyl-3-methyl-5-allyl-hexahydro-1,3,5-triazinone-2 Mixed in a 1:4 to 4:1 ratio, preferably 1:2 to 2:1 ratio.

Substituted uracils The pyrimidinediones of this invention can be mixed with substituted uracils, in the respective proportions listed below. Methods for the preparation of the listed uracils which are novel can be found in copending applications Ser. Nos. 233,952 filed Oct. 29, 1962 and 237,311 filed Oct. 22, 1963.

Mixed in a 1:6 to 6:1 ratio, preferably a 1:4 to 4:1 ratio.

3-cyclohexyl-G-methyluracil 3-cyclohexyl-6-ethyluracil 3-cyclohexy1-6-sec-butyluracil 3-cyclohexyl-6-propyluracil 3 -cyclophentyl-6-methyluracil 3 -cyclohexyluracil Mixed in a 1:6 to 6:1 ratio, preferably a 1:4 to 4:1 ratio.

3-isopropyl-5-brornouracil 3-sec-butyl-5-bromouracil 3-sec-butyl-S-chlorouraeil 3-cyclohexyl-5-bromouracil 3-cyclohexyl-5 -chlorouracil Mixed in a 1:4 to 4:1 ratio, preferably a 1:2 to 2:1 ratio.

3-isopropyl-l-trichloromethylthio-5-bromo- 6-methyluracil 3-cyclohexyl-1-trichloromethylthio-S-bromo- 6-methyluraci1 3 -sec-buty1- l-acetyl-5-bromo-6-methyluracil 3-isopropyl-1-acetyl-5-bromo-6-methyluracil 3-isopropyl-1-trichlorornethylthio-S-chloro- 6-methyluracil This invention will be better understood by referring to the following illustrative examples:

Preparation of compounds EXAMPLE l.PREPARATION OF 3 CYCLOHEXYL-5,6-

DI HYDRO-7-METHYL-5-CYCLOPENTA [D PYRIMIDINE- 2,4(lH,3H)-DIONE A mixture of 142 parts by weight of cyclohexylurea, 170 parts by weight of ethyl 3-methyl-2-cyclopentanonel-carboxylate, parts by weight of p-toluene sulfonic acid and 879 parts by weight of benzene is stirred at reflux for 8 hours. During this time, the water given off by the reaction is trapped out. The solvent is stripped at reduced pressure and the residue is dissolved in 1000 parts by Weight of absolute alcohol containing 80 parts by Weight of sodium methoxide, and is refluxed for 30 minutes. The solvent is stripped at reduced pressure and the residue dissolved in water, cooled, and acidified. The solid is filtered otf, dried, and recrystallized from ethanol to give the desired 3-cyclohexy1-5,6-dihydro-7-methyl-5- cyclopenta-[D]pyrimidine-2,4-(1H,3H)-dione, melting at 201-203 C.

EXAMPLE 2.PREPARATION OF 3(2-METHYLCYCLO- HEXYL)-5,6-DIHYDRO-G-ETHYL 5 CYCLOPENTA[D] PYRIMIDINE-2A(1H,3H)-DIONE A mixture of 184 parts by Weight of ethyl 4-ethyl-2- cyclopentanone-l-carboxylate, 156 parts by weight of 2- methylcyclohexylurea, 10 parts by weight of p-toluene sulfonic acid, and 1000 parts by weight of toluene is stirred at reflux for 6 hours. During this time the water given off by the reaction is trapped out. The solvent is stripped from the resulting solution at reduced pressure. The residue is then dissolved in 793 parts by weight of absolute ethyl alcohol.

To this solution is added a mixture of parts by Weight of sodium methoxide in 300 parts by weight of absolute ethyl alcohol. The mixture is then refluxed for 20 minutes. The solvent is stripped from this mixture and the resulting solid is dissolved in 3000 parts by Weight of water.

This solution is cooled, acidified with excess hydrochloric acid and the solid is filtered off. Recrystallization of this solid from ethanol or acetonitrile gives pure 3(2- methylcyclohexyl 5,6 dihydro-6-ethyl 5 cyclopenta- [D]-pyrimidine-2,4(1H,3H)-dione.

The compounds listed in the following table can be prepared according to the procedures of Example 1 or 2 by substituting equivalent amounts of the listed ureas, and alkyl substituted-2-cycloalka-none-l-carboxylates for those used in the examples:

TABLE I.PREPARED ACCORDING TO PROCEDURES OF EXAMPLE 1 Substituted urea Parts by Ester of the cycloalkanone carboxylate Parts by SubstitutedlD]pyrimidine-2,4 (1H,3H)-dione weight weight product l-ethylpropylurea Ethyl-K-methyl-2-cyclopentanone-l-carboxylate. 176 3-(l-ethylpropy1) -5,6-dihydro-7-methyl 5- cyclopenta[D]pyrimidine-2,4(1H,3H) -dio11e. n-Butylurea 116 Ethy1-3-ethyl-eyclopentanone-Lcarboxylate 190 3-nbuty1-5,6-dihydro-7-ethyl-5-cyelopenta- [D]pyrimidlne-2,4 (111,311) -dione. n-H exylurea 144 Ethyl-3-n-propyl-2-eyclop entunoue-l carboxyl- 204 5,6-dihydro-3-n-hexyl-7-n-propyl 5-eyclopenta ate. [D]pryimidine-2,4 (1H,3H) -dione. Isooctylurea 172 Ethyl-3-nbutyl-2-cyclopentanone-l-carb oxylate 7-n-butyl-5,7-dihydro-3-isooetyl-5-cyclopenta[D]- pyrimidine-2,4 (1H,3H) -dionev 1-Naphthylurean 204 E thyl-3-methyl-2-cyclopentanone-l-carboxylate... 176 7 -methyl-5,6-dihydro-3-(a-napthy1) -5-cyclopenta- D]pyrimidine-2,4(1H,3H)-dione. Tertbutylurea 116 Ethyl-3-methy1-2-cyclohexanone-l-carboxylate.. 201 3-tert-butyl8-methyl-5,6,7,8 tetrahydro-5- eyclohexa[D]pyrimidine-2,4(1H,3H) -di0ne. nO ctylurea 172 Ethyl-3-ethyl-2-cyclohexanone-l-carboxy1ate 215 7,8-diethyl-3-n-oety1-5,6,7,8-tetrahydro-5-eyclohexa[D]pyrimidine2,4(1H,3H) -dione. Cyclooctylurea 17 0 Methyl-3 methyl-2-cyc1opentanone-l-carb oxyl- 3-cyclo0ctyl-5,6-dihydro-7methyl-5-cyelopeutaate. [D]pyrirnidine-2,4(1H,3H)-dione. Cyclopentenylurea 126 do 17 0 3-oyclopentenyl-5,6dlhydro-7-methyl-5-cyclopenta[D]pyrimidine-2,4(1H ,3H) -dione. Fenehylurea 216 do 170 3-Ienohy1-5,G-dihydro-7methyl-5-cyclopenta[D]- pyrimidine-2,4 (1H ,3H) -dione. M ethylurea 74 E thy1-3-sec-buty1-2-cye1ohexan0ne-1-carboxylate 218 7-see-butyl3-methyl-5,6,7,8-tetrahydro-5-cyelohexa[D]pyrimidine-2,4(1H,3H) -dione. 2-methyleyclohexylurea 156 Ethyl-3-methyl-2-eyclop entanone-l-carboxylete. 176 5,6-dihydro-7-methyl-3-(Zanethylcyclohexyl) -5- cyelopenta[D]pyrimidine-2,4(1H,3H) -d1one. S ec-butylurea 116 do 176 3-Sec-blltyl-5,6'dihydro-7-rnethyl-5-cyclopenta- [D]pyrimidine-2,4-(1H,3H) -dione. Isopropylurea 102 do 176 5,6-dihydr0-3-1sopropyl-7-methyl- -cyclopenta- [D]pyrimidine-2,4(1H,3H) -dione. Tert-butylurea 116 do. 176 3-tert-butyl-5,6-dihydro-7-rnethyl-5-cyclopenta- [D]pyrimidine-2,4 (1H,3H) -dione. Cyclohexylurea 142 E thyl-3,5,5-trimethyl-2-cyclopentanone-l-car- 204 3tert-butyl-8-methy1-5,6,7,8-tetrahydro-5-cyclo boxylate. h xa[D]pyrimidine-2,4(1H,3H) -dione. Sec-butylurea 116 d 204 7,8-diethyl-3-n-oetyl-5,6,7,8-tetrahydro-5-cye10- hexa[D]pyrim1dine 2,4(1H,3H) -dlone. Chloronorbornylurea 188. 5 Methyl-3-ethyl 2-cyclopentanone-l-carb oxylate 184 3-chloronorbornyl-5,G-dihydro-7-ethyl-5-eyelopenta[D]pyrimidine-2,4(1H,3H) -dione. B ornylurea 216 do t 184 3-bronyl-5,6-dihydro-7-ethy1-5-cyclopenta[D]- pyrimidine-ZA (1H,3H) -di0ne. Norb ornylurea 154 do 5,6 dihydro-7-ethyl-3-norbornyl-5-cyelopenta[D]- pyrimidine 2,4(1H,3H) -di0ne. Cyclopropylmethylurea- 115 E thyl-3-methyl2'cycloheptan0ne-1-carboxy1ate 216 3-oyelopr0py1methy1-9methyl5,6,7,8-tetrahydro- 5-cyclohepta[D]pyri1nidine-2,4(1H,3H)-dione. 2-methoxyethylurea 118 Ethyl-3-n-butyl-2cyc1oheptanone-1-carboxylate 258 9n-buty1-3-(2-rneth0xy-ethyl) -5,6,7 ,S-tetrahydro- 5-cyclohepta[D]pyrimidine2,4(lH,3H) -dione. Allylurea 100 Ethyl-3-methyl-2-cyclohexanone-1-earboxylate 201 3-allyl8-methyl-5,6,7,8-tetrahydro-5-cyelohexa- [D]pyrin1idine-2,4(1H,3H) -dior1e. D ecenylurea 200 E thyl-3-ethyl-2-cycloheptanone-l-carboxylate 230 3-decenyl-9-ethyl-5,6,7,8-tetrahydro-5-eyclohepta- [D]pyrirnidine-2,4(1H,3H) -dlone. Cyclohexylurea 142 Ethyl-3-methy1-2-cyclohexanone-l-carboxylate. 201 3-eyclohexyl-8-methyl-5,6,7,8-tetrahydro-5-cyclohexalD]pyrim1dine-2,4(1H,3H) -dlone. 2-methylcycl0hexylurea 156 Etl1yl-3 ethyl-Z-eyclohexanone-1-carb0xylate 215 8-ethy1-3-(Z-methylcyclohexyl) -5,6,7,8-tetrahydro- 5-cyclohexa[D]pyrimidine-2,4(1H ,3H) -dlone. Sec-butylurea 116 Ethyl-3-methy1-2-cyclohexanone-1-earb oxylate. 201 3-sec-butyl-8-methyl-5,6,7,8-tetrahydro-5-eyclohexa.[D]pyrimidine-2,4(1H ,3H) -dione. Isopropylurea 102 do 201 3-is0pr0pyl-8-methyl-5,6,7,8-tetrahydro-5-eyclohexa[D]Dyrimidine-2,4 (1H ,3H) -dione. Cyclohexylurea 142 Ethyl-3-methyl-2-cyeloheptanone-l-carboxylate.. 201 3-eyclohexyl-9-methyl-5,6,7,8-tetrahydro-5-cye1oheptalD]pyrimidine-241113151) -dione. 2-methylcyclohexylurea. 156 do 201 9-methyl-3- (2-methyleyclohexyl) -5,6,7,8-tetragydro-5-eyclohexa[D]pyrimid1ne-2,4(1H,3H)-

one. Sec-butylurea 116 do 201 3-see-buty1-5,6,7,8-tetrahydro-9-methyl-fi-cyelohepta[D]pyrimidine-2,4 (1H,3H)-dio11e. Isopropylurea r 102 r do 201 3-isopropyl-9-methy15,6,7,8-tetrahydro-5-cyclohepta[D]pyrimidine-2,4(1H,3H)-dione.

TABLE I.IREI'ARED ACCORDING TO PROCEDURES OF EXAMPLE 1.Coufinued Substituted urea Parts by Ester of the cyeloalkanone carboxylate Parts by Substituted[D]pyrlmidine-2,4(1H,3H) -dione weight weight product Tert-butylurea 116 do 201 3-tert-butyl-9-methyl-5,6,7,8-tetrahydro-5-cyelohepta[D}pyrim1dine-2,4(1H,3H)-dione.

Cyelopentylurea 1% Ethyl--metlryl-Myelopentanone-l-earboxylate.. 187 3-eyelopentyl-5,6-dihydro-6-methy1-5-eyelopenta- [D]pyrimidiue-2,4(1H,3H) dione.

1-(4-methoxycyclo-hexyD- 172 Ethy1-4-ethyl-2-cyclopeutanone-l-carboxylate.. 201 5,6-dihydro-6-ethyl-3(4-methoxyeyclohexyl)-5- urea.

PREPARED ACCORDING TO PROCEDURES eyelopentalD]pyrimidine-2,4(1H,3H)-dlone.

OF EXAMPLES 1 AND 2 1- (3-4dichlor0-cycl0- 211 Ethyl-4-u-propyl-2-eyelopentanonel-carboxyl- 229 5,6-dl hydro-3-(3,4-diehloroeyclohexyl)-6-n-propyl hexyl) -urea.. e. 5-eyc1opents[D]pyrim1dine-2,4(1H,3H) -dione.

Cyelooeteuylurea 168 Methyl i-iospropyl-Z-cyclopentanone-l-carhoxyl- 190 3-cycoloctenyl-fifi-dlhydro-fi iso propyl-5-eyelo e. penta[D]pyrlmldine-2,4(1H,3H) -dlone. Carvacrylurea 191 Methyl-4etl1yl-2-eyelopentanone-l-carboxylate. 187 3-carvacryl-5,6-d1hydro-6-ethyl-5-eye1opentaIDlpyrimld1ne-2,4(1H,3H) -dlone. Isopropylurea 102 Methyl--n-butyl-2-cyclopentanone-I-carboxyl- 190 fi-n-bu tyl-5,G-dihydro-3-isopropyl-5-cyc1openta ate. [D1pyrimidine-2,4(1H,3H)-dione. u-Amylurea 130 Ethy1-4-methyl-Z-cyclopentanone-l-carboxylate. 187 3-n-amy1-5,6-dihydro6-methyl-5-cyclopenta[D]- pyrimidine-2,4011,3H)-dlone.

Bromouorb ornylurea. 231 do 187 3-bromonorbethyl-5,6-dihydro-Gmethyl-fieyclopentaID] pyrimidine-2,4(1H,3H) -dione.

Cyclohetenylurea 156 do 202 H-cyeloheptenyl-5,6-dihydro-6-methyl-5-cyclopenta[D]pyrimidine-2,4(1IL3H) -dine.

D eeahy dronaphthylurea- 196 Ethyl--methyl-2-oyelopentanone-l-carboxylate.. 176 3-decahydronaphthyl-5,6-dihydr0-5-methyl-5- 1- (4-isopr0pyleyel0hexy1)- 185 Ethyl-5-ethyl-2-cye1opentauone1-carboxylate 190 5,6dihydro-5-ethyl-3- (4-isopropylcyclohexyD- urea. 5cyc1openta[D]pyrimidlne-2,4 (1H,3H)-dlone.

1-(1-ethylhexyl) -urea i 158 Ethyl-fi-isopropyl-2-cyelopentanone-l-csrboxyl- 204 5,6-d1hydro-3- (l-ethylhexyl) -5-lsopropyl-5cyelo- 1- (1,1-dimethylbutyD- 144 Ethyl-fi-n-butyl-lZ-cy elopentanone-l-carboxyl- 23D 5-n-buty1-5,6-dihydro-3- (1,1-dlmethylbutyl)-5- urea. ate. eyclopentalD1pyrlmidine-2,4(1H,3H)-dione.

1- (3a,4,5,6,7,7a-hexahydro- 196 Ethyl-5-methyl-2-cyclopentenoned-earboxylate-. 176 5,6-dihydro-3-(3a,4,5,6,7,7a-hexahydro4fl- 4,7-methano-5-indeny1) methano-5-1ndenyl)-5-methyl-5-cyclop enta[D] urea. pyrimidine-2,4 (1H,3H)-dioue.

l- (3e,4,5,6,7,7a-hexahydro- 19B -do 187 5,6-dihydro-3(3a,4,5,6,7,7a-hexanhydro-5- EXAMPLE 3.PREPARATION OF 3-n-BUTYL-5,6DIHY- DRO 5 VINYL-5-VINYL-B-CYCLOPENTA[D]PYRIMI- DIME-2,4 (111,311) -DIONE To a warm stirred slurry of 104 parts by Weight of n-butylurea and 1000 parts by Weight of benzene is added 10 parts by weight of p-toluenesulfonic acid and 180 parts by weight of ethyl 2-cyclopentanone-5-vinyl-lcarboxylate. The slurry is refluxed for 16 hours during which the water given off by the reaction is trapped out.

The resulting solution is decanted and concentrated to an oil.

A solution of 90 parts by weight of sodium methoxide in 1400 parts by weight of ethyl alcohol is added to this oil and the mixture is refluxed for 20 minutes. The solution is then concentrated to dryness and the residue dissolved in 2000 parts by weight of Water.

The aqueous "basic solution is extracted free of neutral impurities with 1500 parts by weight of ether. It is then cooled and acidified to a pH of 5 with hydrochloric acid. Solid, white 3-n-butyl-5,6-dihydro-5-vinyl-5-cpclopenta- [D]pyrimidine-2,4(1H,3H)-dione precipitates, which is filtered and dried.

EXAMPLE 4.PREPARATION OF 3'n BUTYL-5,6-DIHY- DRO 5 e (1,2-DIBROMOE'1HYL) 5 CYCLOPENTA[D] PYRIMIDINEQA (1H,3H) -DIONE A mixture of 46.8 parts of 3-n-butyl-5,6-dihydro-5- vinyl 5 cyclopenta[D]pyrimidine-2,4(1H,3H)-dione is stirred at room temperature in 600 parts of methylene chloride. To this is gradually added 32 parts of bromine. At the end of the addition the reaction mixture is stripped to dryness giving essentially pure 3-n-butyl-5,6-dihydro-5- (1,2 dibromoethyl) 5 cyclopentaIDJpyrimidine- 2,4(1H,3H)-dione.

Compounds Similarly prepared are:

3-cyclohexyl-5,6-dihydro-5-(1,2-dibromoethyl)-5-cyclopenta [D] pyrimidine-2,4( 1H,3H) -dione 3 -cyclohexyl-5,6-dihydro-5-(1,2-dichloroethyl)-5-cyclopenta [D] pyrimidine-2,4-( 1H,3H )-dione 3 -m-chlorophenyl-5,6-dihydro-5-(1,2-dichloroethyl)-5- cyclopenta [D] pyrimidine-2,4 1H,3H) -dione Additional compounds which may be made and are within the scope described for this invention are: 3-hexahydroazepinyl-7-rnethyl-5,6-dihydro-5-cyelopenta [D pyrimidine-2,4( 1H, 3H) -di0ne 8-ethy1-3'piperidin'o-5,6,7,8-tetrahydro-5-cyclohexa [D] pyrimidine-2,4(1H,3H)-dione 3-cyclohexyl-6,7-dimethoxy-S ,6,7, 8-tetrahydro-5-cyclohepta [D] pyrimidine-2,4( 1H,3H) -dione 3-cyclohexyl-6,7-dichloro-5,6,7,8-tetrahydro-5-cyclohe pta [D] pyrimidine-2,4 1H, 3H) -dione 3-n-butyl-5 ,6,7-trichloro-5,6,7,8-tetrahydro-S-cyclohepta [D] pyrimidine-2,4 1H, 3H) -dione 3-cyclohexyl-5,7-dibromo-5,6-dihydro-S-cyclopenta [D] pyrimidine-2,4(1H,3H)-dione 5-bromo-3-cyclohexyl-5 ,6-dihydro-5-cyclopenta[D] pyrimidine-2,4( 1H,3H) -dione 7-bromo-3-cyclohexyl-5,6-dihydro-5-cyclopenta [D] pyrimidine-2,4 1H, 3H) -dione 3-cyclohexy1-6-ethyl-5,6,7,S-tetrahydro-S-cyclohexa [D] pyrimidine-2,4( 1H,3H -dione 3-cyclohexyl-6-propy1-5,6,7,8-tetrahydro-5-cyc1ohexa[D] pyrimidine-2,4(1H,3H)-di0ne 3-cyclohexyl-6-sec-butyl-5,6,7,8-tetrahydro-5'cyclohexa [D] pyrimidine-2,4( 1H,3H) -dione 3-sec=butyl-6-sec-butyl-5,6,7,S-tetrahydro-S-cyclohexa [D] pyrimidine-2,4(1H,3H)-dione 3-cyclohexyl-6,8-diisopropyl-5,6,7,S-tetrahydro-S-cyclohexa [D] pyrimidine-2,4( 1H,3H -di0ne 3-cyclohexyl-8-methoxy-5,6,7,8-tetrahydro-S-cyclohexa [D] pyrimidine-2,4( IH,3H) -dione 3-sec-butyl-6-methoxy-7emethy1-5 ,6,7, 8-tetrahydro-5- cyclohexa [D] pyrimidine-2,4 1H,3H) -dione 3-cyclopropyl-6,7,S-trimethyl-S,6,7,S-tetrahydro-S-cyclohexa [D] pyrimidine-2,4( 1H,3H -dione 6-tert-butyl-8-methyl-3 (2-cyclohexylmethyl) -5,6,7,8-tetrahydro-S-cyclohexa [D pyrimidine-2,4( 1H,3H) dione 3-cyclohexyl-9-isopropyl-6-methy1-5,6,7,8-tetrahydro-5- cyclohexa[D]pyrimidine-2,4(1H,3H)-di0ne 8-methoxy-6-methyl-3-phenyl-5,6,7,8-tetrahydro-5-cyclohexa[D] pyrimidine-2,4( 1H,3H) -dione -isobutyl-3-cyclohexyl-5,6,7,8-tetrahydro-5-cyclohexa [D]pyrimidine-2,4(1H,3H)-dione 3-tert-butyl-6,7-dimethyl-5,6,7,S-tetrahydro-S-cyclohexa [D] pyrimidine-2,4( 1H,3H) -dione 3-sec=butyl-5,6-dihydro-5,7-dimethyl-5-cyclopenta[D] pyrimidine-2,4( 1H,3H) -dione 3-cyclohexyl-5,6-dihydro-5,7-dimethyl-5-cyelopenta [D] pyrimidine-2,4(1H,3H)-dione 3-cyclohexy1-5,6-dihydro-5,7-trimethyl-5-cyclopenta[D] pyrimidine-2,4( l H,3H)-dione EXAMPLE 5.PREPARATION OF 3-CYCLOHEXYL-5,6-DI- HYDRO 7 METHYL--CYCLOPENTA[D]PYRIMIDINE- 2,4(1H,3H)-DIONE Into a solution of 12 parts by weight of sodium hydroxide, 50 parts of ethanol and 100 parts of water is added 62.5 parts by weight of 3-cyclohexyl 5,6-dihydro-7-methyl-5-cyclopenta[DJpyrimidine 2,4(1H,3H) dione. This slurry is heated and stirred until the solids are completely dissolved. The sodium salt of the pyrimidinedione separates on cooling. More of the solid can be forced out of solution by dilution with acetonitrile. The salt is filtered off and dried.

The following salts are prepared according to this method by substituting equivalent quantities of an appropriate substituted pyrimidinedione for the 3-cyclohexyl 5,6 dihydro 7 methyl 5 cyclopenta[D ]pyrimidine-2,4(1H,3H)-dione and the proper hydroxides for sodium hydroxide:

5,6-dihydro-3isopropyl-7-methyl-S-cyclopenta [D] pyrimidine-2,4(1H,3H)-dione potassium salt 3-cyclohexyl-5,6-dihydro-8-methyl-5-cyclohexa[D] pyrimidine-2,4(lH,3H)-dione sodium salt 3-tert-butyl-5,6-dihydro-8-methyl 5-cyclohexa[D] pyrimidine-2,4( lH,3H)-dione sodium salt 3-cyclohexyl-5 ,6-dihydro-9-methyl-5-cyclol1epta [D] pyrimidine-2,4(1H,3I-I)-dione potassium salt EXAMPLE 6.PREPAR'ATION OF 3-CYCLOHEXYL-5,6-DI- HYDRO 7 METHYL5CYCLOPENTA[D]PYRIMIDINE- 2,4(1H,3H)-DIONE, TETRABUTYLAMMONIUM SALT A mixture containing 250 parts of 3-cyclohexyl-5,6- dihydro 7 methyl 5 cyclopenta[D]pyrimidine 2,4 (lH,3H-dione) and 865.8 parts of a one-molar solution of tetrabutylammonium hydroxide in methanol is stirred and heated slightly until solution is complete. The solvent is removed by distillation under reduced pressure. The resulting white solid is essentially pure 3-cyclohexy1-5,6- dihydro 7 methyl 5 cyclopenta[D] pyrimidine 2,4 (lH,3H)-dione, tetrabutylammonium salt.

Other quaternary ammonium salts can be similarly prepared by reacting equivalent amounts of an appropriately substituted pyrimidinedione and a suitable quaternary ammonium hydroxide. The following compounds can be prepared in this fashion:

3 -cyclopentenyl-5 ,6 -d ihydro- S-methyl-S -cyclohexa [D] pyrimidine-2,4(1H,3H)-dione, tertamethylammonium salt 3-bornyl-5,6-dihydro-8-ethyl-5-cyclohexa[D] pyrimidine-2,4( 1H,3H) -dione, trimethylbenzylammonium salt 3-isopropyl-5,6-dihydro-9-methyl-3-cyclohepta[D] pyrimidine-2,4( 1H,3H) -dione, trimethyldodecylammonium salt EXAMPLE 7 .--PREPARATION OF 3-SEC-BUTYL-5,6-DIHY- DRO 8 METHYL-fi-CYCLOHEXA[D]PYRIMID1NE 2,4 (1H,3H)-DI-ONE, PIPERIDINE ADDITION COMPOUND A mixture containing one part of 3-sec-butyl-5,6-dihydro 8 methyl 5 cyclohexa[D] pyrimidine 2,4(1H, 3H)-dione and 4 parts of piperidine is stirred and gently heated until a clear solution is obtained.

By similarly employing equivalent amounts of appropriate pyrimidinedione and nitrogenous bases in place of the .3 sec-butyl-S,6-dihydro- 8-methyl-5-cyclohexa[D]pyrimidine-2,4(lH,3H)-dione and piperidine, the following pyrimidinedione-nitrogenous-base-addition products can be prepared:

3-sec-butyl-7-ethyl-5,6,7,8-tetrahydro-5-cyclohexa[D] pyrimidine-2,4(1H,3H)-dione, triethylenediamine addition compound 3-sec-butyl-6-ethoxy-5 ,6,7,8-tetrahydro 5-cyclohexa [D] pyrimidine-2,4(1H,-3H)-dione, ethylenediamine 3 -sec butyl-6-ethyl-5 ,6,7,8-tetrahydro-5-cyclohexa [D] pyrimidine-2,4(1H,3H)-dione, octylamine addition compound 3-sec-butyl-6-isopropyl-5,6,7,S-tetrahydro-S-cyclohexa [D] pyrimidine-2,4( 1H,3H -dione, dodecylamine addition compound 6-ethyl-3 2-methylcyclohexyl -5 ,6,7,8-tetrahydro- 5 -cycl0hexa[D] pyrimidine-2,4( 1H,3H) -dione, piperidine addition compound EXAMPLE 8.PREPARATION OF 7-METHYL-3-(2-METH- YLCY'CLOHEXYL) 5,6,7,8 TETRAHYDRO 5 CYCLO- HEXA[D]PYRIMIDINE 2,4(1H,3H) DIONE, PIPERI- DINE ADDITION COMPOUND A mixture containing one part 7-methyl-3-(2-methylcyclohexyl) 5,6,7,8 tetrahydro 5 cyclohexa[D]py rimidine-2,4(1H,3H)-dione, and 50 parts of piperidine is stirred and gently heated until a clear solution is obtained.

The following can be prepared in the same fashion:

3-cyclohexyl-5,6-dihydro-7-methyl-5-cyclopenta[D] pyrimidine-2,4(1H,3H)-dione, butylamine addition compound 3-cyclopentyl-5,6-dihydro-8-methyl-5-cyclopenta[D pyrimidine-2,4(1H,3H)-dione, piperidine addition compound 5,6-dihydro-7 methyl-3-phenyl-5-cyclopenta[D] pyrimidine-2,4( 1H,3H) -dione, piperidine addition compound EXAMPLE 9.PREPARATION OF THE 1 1 COMPLEX OF 3 CYCLOHEXYL 5,6 DIHYRO 7 METHYL 5 CY- 'CLOPENTA[D]PYRIMIDINE 2,4(1H,3H)-DIONE WITH PHENOL A mixture of 248 parts of 3-cyclohexyl-5,6-dihydro-7- methyl-S-cyclopenta [D] pyrimidine-2,4( 1H,3H) -dione and 94 parts of phenol is gradually heated until a clear melt forms. The liquid is stirred to assure complete mixing and is then allowed to cool.

EXAMPLE 10.PREPARATION OF THE COMPLEX OF 3 CYCLOHEXYL 5,6 DIHYDRO 7 METHYL 5 CY- CLOPENTA[D]PYRIMIDINE 2,4(1H,3H)-DIONE WITH p-CHL'OROPHENOL A mixture of 248 parts of 3-cyclohexyl-5,6-dihydro-7- methyl-S-cyclopenta [D pyrimidine-2,4-( 1H,3H) -dione and 128 parts of p-chlorophenol is gradually heated until a clear melt forms. The liquid is stirred and allowed to cool.

The following complexes can be prepared in a similar fashion by replacing the 3-cyclohexyl-5,6-dihydro-7- methyl 5 cyclopenta[D]pyrimidine 2,4(1H,3H)- dione and p-chlorophenol with equivalent amounts of appropriate pyrimidinediones and phenols:

5 ,6-dihydro-3-isopropyl-7 -methyl-5-cyclopenta[D] pyrimidine-2,4 1H,3H -dione, pentachlorophenol complex until the particles of active material are less than microns in diameter:

Percent 3 cyclohexyl 5,6 dihydro 7 methyl 5 cyclopenta[D]pyrimidine-2-,4(lH,3H)-dione 30.0 Sodium lignin sulfonate 5.0 Hydrated attapulgite 1.5 Water 63.5

This stable suspension, when diluted with water and when applied at the rate of 25 pounds of active ingredient per acre in 100 gallons of water, gives excellent control of such annual weeds as crab grass, foxtail, wild rye, wild barley, bachelor buttons, and lambs quarters growing in a parking lot.

The following substituted pyrimidinediones can be formulated similarly. When applied in a like fashion, in equivalent amounts, they also give good herbicidal results:

EXAMPLE 12.--W'ETTABLE POWDER The following components are blended, then micropulverized until substantially all the solids are under 50 microns in particle size, then reblended to homogeneity. They are then passed through an air attrition mill, such as an air reductionizer, to reduce the particle size to under 10 microns:

Percent 3-tert-butyl-6-methyl-5,6,7,8-tetrahydro-5- cyclohexa[D]pyrimidine-2,4(lH,3H)-dione 80.0 Dioctyl sodium sulfosuccinate concreted with sodium benzoate (Aerosol OTB) 2.0 Partially desulfonated sodium lignin sulfonate 1.0 Calcined, non-swelling montmorillonoid type clay (Pikes Peak clay) 17.0

This composition is used for pre-emergence application in sugar cane. It is dispersed in 40 gallons of water and sprayed with a pressure sprayer. At 0.5 to 2.0 pounds of active ingredient per acre, excellent control of lambs quarters, purslane, mustard, crab grass, foxtail, and water grass is obtained.

The following compound can also be used as indicated above and gives good weed control: 3-cyclohexyl-5,6-dihydro-7-methyl-S-cyclopenta[D] pyrimidine-ELM1H,3H)-dione 20 EXAMPLE 13.PELLETS Percent 3-cyclohexyl-5,6-dihydro-7-methyl-5- cyclopenta[D]pyrimidine-2,4(lH,3H)-dione 6.67 3-sec-butyl-S-brorno-6-methyluracil 3.33 Sodium sulfate, anhydrous 10.00 California sub-bentonite clay 80.00

These ingredients are blended, micropulverized, pugmilled with 15-20% Water, and extruded through /8 inch holes. The extrusions are cut into A; inch lengths, dried, and screened.

This formulation keeps lumber yards free of weeds. The pellets are distributed in the spring with a seeder at 20 pounds (actives) per acre. The lumber-yard stacking area is kept free of such pernicious weeds as crab grass, ragweed, plantain, pigweed, Russian thistle, fall panicum, goat weed, cheat, and seedling Johnson grass.

EXAMPLE l4.-GRANULES Percent 3-isopropyl-7-methyl-5,6,7,8-tetrahydro-5- cyclohexa[D]pyrimidine-2,4(1H,3H)-dione 5 8l5 mesh granular, expanded vermiculite 95 This granular composition is prepared by dissolving the active material in water and spraying it upon the granules while they are being tumbled. The granules are then dried.

These granules are applied at 25 pounds of active ingredient per acre to mixed annual and perennial vegetation, including quackgrass, plantain, crab grass, barnyard grass, volunteer wheat, bachelor buttons and chickweed, growing under cyclone fences, around highway markers, along fence rows, and around oil tank installations. Excellent Weed control is obtained.

The following compounds can be formulated in a like manner, and when used in herbicidally equivalent amounts, will give good weed control:

EXAMPLE 15.EMULSIFIABLE OIL SUSPENSION The following components are mixed together and milled in a roller mill, pebble mill, or sand mill until substantially all the particles of the active component are under 10 microns in size. The resulting suspension may be emulsified in water or diluted further with weed oils for spray application.

Percent 5,6 dihydro 7 methyl-3-phenyl-5-cyclopenta[D] pyrimidine-2,4(lH,3H)-dione 25 Blend of polyalcohol carboxylic esters and oil soluble petroleum sulfonates 6 Isophorone 69 This formulation is diluted with gallon of Lion Herbicidal Oil-No. 6 and applied at 20 to 30 pounds of active ingredient per acre for the control of morning glory, yarrow, ragweed, wild carrot, water grass, barnyard grass, crab grass, foxtail and pigweed growing along fence rows. Excellent control is obtained.

Percent 3-cyclohexyl-5,6-dihydro-7-rnethyl cyclopenta [D] pyrimidine-2,4(1H,3H)-dione Sodium silicate 74 Sodium dioctyl sulfosuccinate 1 These components are blended and micropulverized.

Ten pounds of this formulation are dissolved in 100 gallons of water containing 0.4% of trirnethylnonyl ether of polyethylene glycol. Three hundred gallons of this solution per acre are applied to a germinating stand of crab grass, black grass (Alopec Urus sp.), annual bluegrass, Kentucky bluegrass, foxtail, barnyard grass, chickweed and wild mustard. Good control of these weeds is obtained.

The following compounds when similarly formulated give good weed control.

3 l-ethylpropyl) -5,6-dihydro-7-rnethyl-S-cyclopenta- [D] pyrimidine-2,4( 1H,3H -dione 3-n-butyl-5,6-dihydro-7-ethyl-5-cyclopenta- [D pyrimidine-2,4 1H,3H) -dione 5,6-dihydro-3-n-hexyl-7-n-propyl-5-cyclopenta- [D] pyrimidine-2,4( 1H,.3H) -dione 7 -n-butyl-5 ,6-dihydro-3-isooctyl-5 -cyclopenta- [D] pyrimidine-2,4( 1H,3H -dione 7-methyl-5,6-dihydro-3- a-naphthyl) -5-cyclopenta- [D pyrimidine-2,4 1H,3H -dione 3-tert-butyl-8-methyl-5,6,7,8-tetrahydro-S-cyclohexa- [D] pyrimidine-2,4 1H,3H) -dione 3-cycloocty1-5,6-dihydro-7-methyl-5-cyclopenta- [D]pyrimidine2,4(1H,3H)-dione 3-cyclopentenyl-5,6-dihydro-7-methyl-5-cyclopenta- [D] pyrimidine-2,4( 1H,3H) -dione 3-fenchyl-5,6-dihydro-7-methyl-5-cyclopenta- [D] pyrimidine-2,4 1H,3H -dione 7-sec-butyl-3-methyl-5 ,6,7 ,8-tetrahydro 5 -cyc1ohexa- [D] pyrimidine-2,4 1H,3H -dione 5 ,6-dihydro-7-methyl-3- (2-methylcyclohexyl) -5 cyclopenta [D] pyrimidine-2,4 1H,3H) -dione EXAMPLE 17.-\VETTABLE POWDER Percent 3-cyclohexy1-8-methyl-5,6,7,8-tetrahydro 5 cyclohexa[D]pyrimidine2,4-(lH,3H)-dione 40.0 3-(3,4-dichlorophenyl) 1,1-dimethylurea 20.0 Alkyl naphthalene sulfonate, Na salt 1.5 Low viscosity methyl cellulose 0.5 Attapugite clay 38.0

A wettable powder is prepared by blending these components and then micropulverizing the mixture until the particles are below 50 microns in size.

This formulation controls weeds along railroad rightsof-way. Applied in the spring in about 100 gallons of water and at the rate of 25 pounds of active ingredients per acre, the formulation gives good control of annual ryegrass, bromegrass, ragweed, henbit, goldenrod, field daisy, buckhorn plantain, water grass, and volunteer rye.

The following compounds when similarly formulated give good weed control:

3 -sec-butyl-5,6-dihydro-7-methyl-5-cyclopenta- [D] pyrimidine-2,4( 1H,3H) -dione 5,6-dihydro-3 -isopropyl-7-methyl-5-cyclopenta- [D] pyrimidine2,4( 1H,3H) -dione 3 -tert-butyl-5 ,6-dihydro-7 -methyl-5-cyclop enta- [D] pyrimidine-2,4( 1H, 3H) -dione 22 What is claimed is: l 1. A method for the control of undesirable vegetation, said method comprising applying to a locus to be protected from such vegetation a herbicidally effective amount of a compound selected from the compounds of the formula i I! Ya I T Yum) T\ (last 0 HO- HR I I: R R. R1

where:

R is selected from the group consisting of alkyl of 1 through 10 carbon atoms,

substituted alkyl of 1 through 10 carbon atoms, wherein said substituent is selected from the group consisting of bromine, chlorine, hydroxy, alkoxy, alkoxycarbonyl, dialkylamino, and cyano,

aryl of 6 through 14 carbon atoms,

substituted aryl of 6 through 14 carbon atoms, wherein said substituent is selected from the group consisting of chlorine, bromine, fluorine, phenyl, alkoxy, alkyl, nitro, trifluoromethyl, 1,2-tetramethylene, and 1,2-trimethylenylene,

aralkyl of 7 through 15 carbon atoms,

substituted aralkyl of 7 through 15 carbon atoms, wherein said substituent is selected from the group consisting of chlorine, alkyl, nitro, and alkoxy,

tetrahydronaphthylalkyl,

alkenyl of 3 through 10 carbon atoms,

alkynyl of 3 through 10 carbon atoms,

substituted cycloalkyl of 3 through 12 carbon atoms, wherein said substituent is selected from the group consisting of bromine, chlorine, methoxy, and alkyl,

cycloalkenyl of 4 through 12 carbon atoms,

substituted cycloalkenyl of 4 through 12 carbon atoms, wherein said substituent is selected from the group consisting of bromine, chlorine, methoxy, and alkyl,

cycloalkyl alkyl of 4 through 13 carbon atoms,

eycloalkenyl alkyl of 5 through 13 carbon atoms,

(substituted cycloalkyl) alkyl of 5 through 14 carbon atoms, wherein said substituent is selected from the group consisting of bromine, chlorine, methoxy, and alkyl,

(substituted cycloalkenyl)alkyl of 5 through 14 carbon atoms, wherein said substituent is selected from the group consisting of bromine, chlorine, methoxy, and alkyl,

cyano,

piperidino,

morpholino,

tetrahydro-4H-1,4-thiazin-4-yl,

4-alkyl-1-piperazinyl, wherein said alkyl portion contains from 1 through 4 carbon atoms,

substituted 4-a1kyl-1-piperazinyl, wherein said alkyl portion contains from 1 through 4 carbon atoms and said substituent is 1 through 4 methyl groups on said ring, dihydro-4H-1,3,5-dioxazin-5-y1, 1-alkyl-3-pyrazolin-2-y1, wherein said alkyl portion contains from 1 through 4 carbon atoms, 2,4,6-trimethyldihydro-4H-1,3,5 diathiazin -5 -yl, 1,2,3,4-tetrahydro-2-isoquinolinyl,

LO-phenoxazinyl,

l0-phenothiazinyl;

R R and R are each selected from the group consisting of hydrogen,

23 alkyl of 1 through 4 carbon atoms, haloalkyl of 1 through 4 carbon atoms, 'alkoxy of 1 through 4 carbon atoms, alkylthio of 1 through 4 carbon atoms, and alkenyl of 2 through 4 carbon atoms;

Y is halogen;

n is a number 3 through 5;

m is selected from the group consisting of and 1; with the proviso that when R R and R are hydrogen, in is 1.

2. The method of claim 1 wherein the active compound is 3-cyclohexyl-5,6-dihydro 7 methyl 5 cyclopenta [D] pyrimidine-2,4(IH,3H)-dione.

3. The method of claim 1 wherein the active compound is 3 sec-butyl 5,6, dihydro 7 methyl 5 cyclopen ta [D] pyrimidine-2,4 1H,3H) -dione.

4. The method of claim 1 wherein the active compound is 5,6 dihydro 3 isopropyl 7 -methyl 5 -cyclopenta [D] pyrimidine-2,4( 1H,3H) -di0ne.

5. The method of claim 1 wherein the active compound is 3 tert butyl 5,6 dihydro 7 methyl 5 cyclopenta[D]pyrimidine-2,4(1H,3H)-dione.

6. The method of claim 1 wherein the active compound is 3 cyclohexyl 8 methyl 5,6,7,8 tetrahydro 5 cyclohexa [D] pyrimidine-2,4 1H,3H -dione.

7. The method of claim 1 wherein the active compound 24 is 3 sec butyl 8 methyl 5,6,7,8 tetrahydro 5 cyclohexa[D]pyrimidine-2,4(1H,3H)-dione.

8. The method of claim 1 wherein the active compound is 3 cyclohexyl 6 methyl 5,6,7,8 tetrahydro 5 cyclohexa [D] pyrimidine-2,4( 1H,3H) -dione.

9.. The method of claim 1 wherein the active compound is 3 sec butyl 3 cyclohexyl 6 methyl 5,6,7,8 tetrahydro 5 cyclohexa[D]pyrimidine 2,4(1H,3H) dione.

References Cited UNITED STATES PATENTS 2/1966 Soloczenski 71-25 OTHER REFERENCES JAMES O. THOMAS, 111., Primary Examiner.

US. Cl. X.R. 

